Predictive value of EGFR mutation in non-small-cell lung cancer patients treated with platinum doublet postoperative chemotherapy.

The mutation status of tumor tissue DNA (n = 389) of resected stage II-III non-squamous non-small-cell lung cancer (Ns-NSCLC) was analyzed using targeted deep sequencing as an exploratory biomarker study (JIPANG-TR) for the JIPANG study, a randomized phase III study of pemetrexed/cisplatin (Pem/Cis) vs vinorelbine/cisplatin (Vnr/Cis). The TP53 mutation, common EGFR mutations (exon 19 deletion and L858R), and KRAS mutations were frequently detected. The frequency of the EGFR mutation was significant among female patients. Patients with an EGFR mutation-positive status had a significantly shorter recurrence-free survival (RFS) time (24 mo vs not reached) (HR, 1.64; 95% CI, 1.22-2.21; P = .0011 for EGFR mutation status). Multivariable analysis identified both the pathological stage and EGFR mutation status as independent prognostic factors for RFS (HR, 1.78; 95% CI, 1.30-2.44; P = .0003 for disease stage; and HR, 1.57; 95% CI, 1.15-2.16; P = .0050 for EGFR mutation status). This study demonstrated that the EGFR mutation has either a poor prognostic or predictive impact on a poor response to postoperative chemotherapy with platinum doublet chemotherapy for stage II-III Ns-NSCLC patients. This result supports a role for mandatory molecular diagnosis of early-stage Ns-NSCLC for precision oncology and signifies the importance of adjuvant for the 3rd generation tyrosine kinase inhibitor rather than platinum-based chemotherapy. This study is registered with the UMIN Clinical Trial Registry (UMIN 000012237).

The C-reactive protein to albumin ratio is a prognostic factor for stage I non-small cell lung cancer in elderly patients: JACS1303.

PURPOSE: To establish the prognostic significance of C-reactive protein (CRP) and albumin in octogenarians with non-small cell lung cancer (NSCLC) based on the study of the Japanese Association for Chest Surgery (JACS 1303). METHODS: A total of 618 octogenarians with pathological stage I NSCLC, who underwent pulmonary resection, were included in the analysis. We conducted multivariable Cox regression analysis to evaluate the CRP to albumin ratio (CAR) as a potential prognostic factor. Other clinicopathological factors were also evaluated. RESULTS: The median age was 82 years. Operations included lobectomy (n = 388; 62.8%) segmentectomy (n = 95; 15%), and wedge resection (n = 135; 22%). Pathological stage IA was diagnosed in 380 (61.5%) patients. The 3-year (OS) and cancer-specific survival (CS) rates were 86.7% and 94.6%, respectively. OS was significantly higher for patients with low CAR (< 0.106) than for those with high CAR (≥ 0.106) (hazard ratio = 3.13, 95% confidence interval: 1.99-4.93, p < 0.0001). Univariate analysis identified sex, poor performance status, smoking status, comorbidity, solid tumor, histology, high Glasgow prognostic scale, and high CAR as significant prognostic factors. Multivariate analysis identified only the CAR as a significant prognostic factor for both OS and CS. CONCLUSIONS: Our analysis of the nationwide data demonstrated that the CAR is a useful prognostic factor for elderly patients with stage I NSCLC.

Tumor mutation burden as a biomarker for lung cancer patients treated with pemetrexed and cisplatin (the JIPANG-TR).

The JIPANG study is a randomized phase III study of pemetrexed/cisplatin (Pem/Cis) versus vinorelbine/cisplatin (Vnr/Cis) for completely resected stage II-IIIA non-squamous non-small cell lung cancer (Ns-NSCLC). This study did not meet the primary endpoint (recurrence-free survival, RFS) but Pem/Cis had a similar efficacy to Vnr/Cis with a better tolerability. Tumor mutation burden (TMB) is thought to have a predictive value of immune checkpoint inhibitors. However, the relevance of TMB to cytotoxic chemotherapy remains unknown. This exploratory study investigates the relationship between tumor mutation profiles and clinical outcome of Pem/Cis. Formalin-fixed, paraffin-embedded tumor tissues (n = 389) were obtained from the patients. Mutation status of tissue DNA was analyzed by targeted deep sequencing. Epidermal growth factor receptor (EGFR) mutations were detected frequently in Ns-NSCLC (139/374). Patients without any EGFR mutations experienced longer RFS in the Pem/Cis arm versus Vnr/Cis arms. Pem/Cis in patients with high TMB (≥12-16 mut/Mb) tended to have improved survival. In patients with wild-type EGFR, TMB ≥ 12 mut/Mb was significantly associated with improved RFS with Pem/Cis versus Vnr/Cis (not reached vs 52.5 months; hazard ratio (HR) 0.477). It could be proposed that TMB was predictive of RFS benefit with Pem/Cis versus Vnr/Cis in Ns-NSCLC. Further investigation is required to determine whether TMB combined with EGFR mutation status could be used as a predictive biomarker.

Survival of Octogenarians with Early-Stage Non-small Cell Lung Cancer is Comparable Between Wedge Resection and Lobectomy/Segmentectomy: JACS1303.

BACKGROUND: Anatomic resection with lymph node dissection or sampling is the standard treatment for early non-small cell lung cancer (NSCLC), and wedge resection is an option for compromised patients. This study aimed to determine whether wedge resection can provide comparable prognoses for elderly patients with NSCLC. METHODS: The study analyzed the clinicopathologic findings and surgical outcomes during a median follow-up period of 39.6 months for 156 patients with solid dominant (consolidation-to-tumor ratio > 0.5) small (whole tumor size ≤ 2 cm) NSCLC among 892 patients 80 years of age or older with medically operable lung cancer between April 2015 and December 2016. RESULTS: The 3-year overall survival (OS) rates after wedge resection and after segmentectomy plus lobectomy did not differ significantly (86.5 %; 95 % confidence interval [CI], 74.6-93.0 % vs 83.7 % 95 % CI, 74.0-90.0 %; P = 0.92). Multivariable Cox regression analysis of OS with propensity scores showed that the surgical procedure was not an independent prognostic predictor (hazard ratio [HR], 0.84; 95 % CI, 0.39-1.8; P = 0.64). The 3-year OS rates were slightly better after wedge resection for 97 patients who could tolerate lobectomy than after segmentectomy plus lobectomy (89.4 %; 95 % CI, 73.8-95.9 % vs 75.8 %; 95 % CI, 62.0-85.2 %; P = 0.14). The cumulative incidence of other causes for death was marginally higher after segmentectomy plus lobectomy than after wedge resection (P = 0.079). CONCLUSIONS: Wedge resection might be equivalent to lobectomy or segmentectomy for selected patients 80 years of age or older with early-stage NSCLC who can tolerate lobectomy.

[Securing and Treatment of Interlobar Pulmonary Artery in Severe Insufficient Interlobar Fissure of the Lung].

There are 2 surgical approaches to secure and treat interlobar pulmonary artery in severe insufficient interlobar fissure of the lung. One is an interlobar approach which is called "fissure first technique". This approach is standard, but sometimes difficult to secure interlobar artery safely. So, lung parenchyma injury and accidental bleeding from the pulmonary artery become troublesome problems. On the other hand, hilar approach without contacting to interlobar fissure which called "hilar first technique" is very useful to avoid lung parenchyma injuries. There are some knack and pitfalls in every lobe of the lung. The key of this approach is to be familiar with the anatomical position of pulmonary artery running by confirming preoperative 3-dimensional computed tomography( 3D-CT). In the final step of this technique cutting the interlobar line exactly is more important to prevent atelectasis and congestion of residual lung. It is very important for thoracic surgeons to know the details of both approaches in the surgical treatment of severe insufficient interlobar fissure of the lung.

Podoplanin expression in cancer-associated fibroblasts predicts unfavourable prognosis in patients with pathological stage IA lung adenocarcinoma.

AIMS: Podoplanin expression in cancer-associated fibroblasts (CAFs) has been proposed as an unfavourable indicator in squamous cell carcinoma of the lung, but little is known about its clinical significance in early-stage lung adenocarcinoma. We evaluated the prognostic impact of podoplanin expression in patients with pathological stage (p-stage) IA lung adenocarcinoma as categorised by the 8th edition of the tumour-node-metastasis classification for lung cancer. METHODS AND RESULTS: Immunohistochemical analyses using anti-podoplanin antibody were performed on resected specimens from 158 patients with p-stage IA lung adenocarcinoma. When more than 10% of cancer cells or CAFs showed immunoreactivity with podoplanin, the specimens were classified as podoplanin-positive. Podoplanin-positive status in cancer cells (n = 8) was not correlated with clinicopathological factors or with patient prognosis. Podoplanin-positive status in CAFs (n = 41) was correlated significantly with poorer tumour differentiation (P < 0.001), the presence of lymphatic invasion (P < 0.001) and high-grade (solid and/or micropapillary) components constituting ≥1% of the entire tumour (P < 0.001). The log-rank test showed that podoplanin-positive status in CAFs was associated significantly with shorter disease-free survival (DFS) (P < 0.001) and disease-specific survival (P = 0.015). In Cox's multivariate analysis, podoplanin-positive status in CAFs had the most significant effect on shorter DFS [hazard ratio (HR) = 4.411, P = 0.004], followed by the presence of high-grade components (HR = 3.581, P = 0.013). CONCLUSIONS: Podoplanin expression in CAFs could be an independent predictor of increased risk of recurrence in patients with p-stage IA lung adenocarcinoma.

[Current Status and Future Prospect of Robot-assisted Thoracoscopic Surgery].

As surgical robots have widely spread, verification of their usefulness in the general thoracic surgery field is required. The most favorable advantage of robot-assisted surgery is the markedly free movement of joint-equipped robotic forceps under 3-dimensional high-vision. Accurate operation makes complex procedures straightforward and may overcome weak points of previous thoracoscopic surgery. Robot-assisted surgery for lung cancer and mediastinal disease have been safely introduced and initial results have shown favorable. It is still at the stage of clinical research, but recently a lot of merits of robot-assisted thoracic surgery are proved. Although safety management, education and significant cost are also important issues, the robotic-assisted thoracoscopic surgery will become one of the surgical options in minimally invasive surgery.

[Robot-Assisted Thoracoscopic Surgery for Lung Cancer].

In addition to conventional video-assisted thoracic surgery(VATS)as minimallyinvasive surgeryfor lung cancer, medical insurance system of robot-assisted thoracoscopic surgery(RATS)byusing da Vinci Surgical System®(DVSS)is just adapted from this spring. Although VATS is widelydiffused in clinical practice, it is recommended as grade C1(considerable)in the latest lung cancer medical guideline. On the other hand, it has been noticed that RATS is attractive and expected to cover the disadvantages of conventional VATS. In the comparison of both VATS and RATS lobectomyfor lung cancer, theyhave been reported to be comparable in safetyand efficacy, but RATS is superior at the viewpoint of good operabilityand faster learning curve. However, high costs and the longer operative time in RATS are of a concern. Experience of RATS is still in the initial phase, however from now on RATS is graduallyinfiltrating and expected to demonstrate the improvement of perioperative outcome. Especially, manyinstitutes have just began to introduce robotic surgeryin general thoracic field after the adaption of medical insurance. So, safetyand sure spread of RATS is an urgent and important issue in our field. Of course, while coexisting with VATS, it is important to verifythe efficacyof RATS.

Simplified comorbidity score for elderly patients undergoing thoracoscopic surgery for lung cancer.

PURPOSE: We investigated the efficiency of the Simplified Comorbidity Score (SCS) for predicting postoperative complications and prognosis in elderly patients undergoing video-assisted thoracoscopic surgery (VATS) for lung cancer. METHODS: We reviewed 216 patients aged 75 years or older, who underwent pulmonary resection by VATS for lung cancer between January, 2005 and December, 2012. The SCS assigns different scores to patients' comorbidities; namely, smoking (n = 7); diabetes mellitus (n = 5); renal insufficiency (n = 4); and respiratory, neoplastic, and cardiovascular comorbidities or alcoholism (n = 1 each). Patients were divided into a high SCS group (SCS ≥ 9; n = 154) and a low SCS group (<9; n = 62), for a comparative analysis of differences in perioperative factors and prognoses. RESULTS: Limited resection was more frequent in the high SCS group (58 %) than in the low SCS group (40 %; P = 0.02). Postoperative complications were more frequent in the high SCS group (45 %) than in the low SCS group (15 %; P < 0.01). A logistic regression analysis revealed that a high SCS was significantly predictive of postoperative complications (odds ratio 2.7; P = 0.02). The 5-year overall survival rate was 79 % for the low SCS group and 52 % for the high SCS group (P < 0.01). CONCLUSIONS: The SCS can predict the likelihood of postoperative complications and prognosis of elderly patients with VATS-treated lung cancers.

Thin-section computed tomography findings of lung adenocarcinoma with inherent metastatic potential.

PURPOSE: The solid component of lung ground-glass nodules on thin-section computed tomography (TSCT) reflects cancer cell progression and invasiveness. The purpose of this study was to clarify the cut-off value of preoperative TSCT findings in treating a lesion suspected of being adenocarcinoma and to recognize the timing of surgical resection for lung nodules. METHODS: We reevaluated the TSCT findings in 392 patients with clinical stage IA lung adenocarcinoma who underwent surgical resection between 2003 and 2007. We identified the clinical parameters that were most useful for predicting recurrence and identified a cut-off level for each parameter. RESULTS: Recurrence was observed in 75 (19 %) of 392 patients (median follow-up: 7 years). The size of internal consolidation of a lung nodule (SCL) and the ratio of the SCL to the maximum tumor diameter (C/T ratio) were extracted as independent factors that predicted recurrence. Only 1 (0.3 %) patient each with a lung nodule C/T ratio ≤0.5 and SCL ≤10 mm recurred. These conditions were associated with a significantly better overall survival and recurrence-free survival. CONCLUSION: In patients with clinical stage I lung adenocarcinoma with a C/T ratio ≤0.5 and/or SCL ≤10 mm on TSCT, surgery is extremely likely to achieve a cure.

Cytoplasmic expression of maspin predicts unfavourable prognosis in patients with squamous cell carcinoma of the lung.

AIMS: Maspin is known to be a tumour suppressor protein, and its prognostic significance in patients with several types of cancer, including lung squamous cell carcinoma (SCC), has been reported. However, its prognostic impact on lung SCC has been controversial. We explored the prognostic value of maspin expression with particular reference to its subcellular localization in patients with lung SCC. METHODS AND RESULTS: Paraffin-embedded tissue samples from 101 curatively resected patients with lung SCC were analysed immunohistochemically using an antibody for maspin. Maspin positivity was defined as strong expression in only the cytoplasm and observed in 25 patients (24.6%). It correlated significantly with the presence of lymph node metastasis (P = 0.006) and higher pathological stage (P = 0.003). The patients were followed-up for 2-119 months (median: 50 months), and the maspin-positive group had shorter disease-free survival (DFS) and disease-specific survival (DSS) by log-rank test (P = 0.002, P = 0.016, respectively). Multivariate analysis revealed that the status of maspin was the only independent prognostic factor for DFS and DSS (P = 0.017, P = 0.047, respectively). CONCLUSIONS: Cytoplasmic expression of maspin could be an independent unfavourable prognostic indicator in patients with lung SCC.

Distribution and Prevalence of Locoregional Recurrence after Video-Assisted Thoracoscopic Surgery for Primary Lung Cancer.

Background The aim of this study is to evaluate cases with locoregional recurrence after video-assisted thoracoscopic surgery (VATS) for primary lung cancer. Methods We reviewed 248 patients with primary lung cancer who underwent lobectomy or segmentectomy with mediastinal lymph node dissection by VATS between January 2005 and December 2011. Locoregional recurrence is defined as per its occurrence in (1) bronchial stump or lung parenchymal cut end, (2) ipsilateral pleura, and (3) ipsilateral hilar and mediastinal lymph nodes, and we analyzed recurrence rate and significant associated factors for locoregional recurrence by logistic regression analysis. Results There were 47 cases of postoperative recurrence, which consisted of 26 distant, 6 locoregional and distant, and 15 locoregional recurrences. The locoregional recurrence rate was 6.0%. Of the 15 locoregional recurrence cases, there were two cases of bronchial stump and lung parenchyma cut end (0.4%), five cases of ipsilateral pleura (2.0%), and eight cases of ipsilateral hilar and mediastinal lymph nodes (3.2%). Pleural and lymphovascular invasion and advanced stages were significant associated factors in univariate analysis. Multivariate analysis revealed that advanced stages were only a significant associated factor for locoregional recurrence (p < 0.01, odds ratio: 3.3). Conclusion Although locoregional recurrence rates of our surgical treatments for primary lung cancer by VATS might be acceptable, we should explore more effective modalities against pathologically proven local advanced lung cancer for preventing not only distant but also locoregional recurrences.

Cytoplasmic maspin expression is a predictor of poor prognosis in patients with lung adenocarcinoma measuring <3 cm.

AIMS: Maspin is known to be a tumour suppressor protein, and few studies focused upon its prognostic significance in patients with small-size lung adenocarcinoma have been reported; however, its clinical significance remains controversial. We explored the prognostic value of maspin with particular reference to its subcellular localization in patients with resected lung adenocarcinoma measuring <3 cm. METHODS AND RESULTS: Immunohistochemical analyses were performed on resected 110 specimens of lung adenocarcinoma measuring <3 cm. Maspin positivity was defined as strong expression in only the cytoplasm and was observed in 27 patients (24.5%). It correlated significantly with the presence of lymph node metastasis (P = 0.009) and micropapillary component (P < 0.001). The patients were followed-up for 6-88 months (median: 71 months), and the maspin-positive group had shorter disease-free survival (DFS) and overall survival (OS) by log-rank test (P < 0.001, P < 0.001, respectively). Using Cox's multivariate analysis, the status of maspin was an independent prognostic factor for DFS and OS (P = 0.004, P = 0.022, respectively), as well as lymph node metastasis. CONCLUSIONS: Cytoplasmic maspin expression could be an independent poor prognostic indicator of patients with lung adenocarcinoma measuring <3 cm.

[Current status and future prospects of robotic surgery for lung cancer].

As the use of robotic surgery has widely spread, its usefulness in the field of general thoracic surgery needs to be verified. The biggest advantage of robotic surgery is the remarkably free movement of joint-equipped robotic forceps under 3-dimensional high vision. An accurate operation makes complex procedures straightforward and may overcome the disadvantages of previous thoracoscopic surgery. Robotic surgery for lung cancer has been safely introduced, and the initial results have been favorable. While still at the stage of clinical research, it is expected to be useful in hilar exposure, lymph node dissection, and suturing of lung parenchyma or bronchus. We considered robotic surgery for lung cancer surgery because of its ability to facilitate both thoracotomy and minimally invasive video-assisted thoracic surgery. Robotic thoracic surgery has not been sufficiently examined for its usefulness, and other major issues such as safety management, education, and significant cost need to be addressed. However, it may become an extension of thoracoscopic surgery, and studies showing its usefulness for primary lung cancer have been increasing. Two urgent issues are its use in advanced medical care and national heal th insurance coverage.

A comparative study of robot-assisted thoracoscopic surgery and conventional approaches for short-term outcomes of anatomical segmentectomy.

OBJECTIVES: Since anatomical segmentectomy requires meticulous dissection of the segmental pulmonary vessels and bronchus, robot-assisted thoracoscopic surgery (RATS) has been widely adopted in recent years. We investigated the usefulness of RATS segmentectomy by comparing perioperative outcomes with conventional approaches including open thoracotomy or video-assisted thoracoscopic surgery (VATS). We compared perioperative outcomes of segmentectomy between RATS and conventional approaches including open thoracotomy or video-assisted thoracoscopic surgery (VATS). METHODS: This single-institutional retrospective study comprised 231 patients with primary lung cancer who underwent segmentectomy by RATS or conventional approaches between January 2011 and December 2022. Surgical outcomes and postoperative complications were analyzed among patients whose background factors were adjusted by propensity score matching (PSM). RESULTS: Before PSM, there were significant differences in age, smoking status, and types of segmentectomy. After PSM, 126 patients (63 patients in each group) were included in this analysis. The RATS group had significantly shorter operative time (154 vs 210 min; p < 0.01), fewer bleeding amounts (10 vs 40 mL; p < 0.01), and shorter duration of chest drainage (2 vs 2 days; p = 0.04) than the conventional-approach group. There was no significant difference in the incidence of all complications; however, the incidence of postoperative pneumonia was significantly lower than in the conventional-approach group (p = 0.02). CONCLUSIONS: RATS segmentectomy is proposed to be useful. It was suggested that RATS segmentectomy may be useful with better perioperative results than the conventional approach. Further studies on oncological long-term outcomes and cost-benefit comparisons are needed.

Early chest tube removal regardless of drainage volume after anatomic pulmonary resection: A multicenter, randomized, controlled trial.

OBJECTIVES: This study aimed to evaluate the safety and feasibility of early chest tube removal after anatomic pulmonary resection, regardless of the drainage volume. METHODS: We conducted a multicenter, randomized, controlled, noninferiority trial. Patients with greater than 300 mL drainage volume during postoperative day 1 were randomly assigned to group A (tube removed on postoperative day 2) and group B (tube retained until drainage volume ≤300 mL/24 hours). The primary end point was the frequency of respiratory-related adverse events (grade 2 or higher based on the Clavien-Dindo classification) within 30 days postoperatively. RESULTS: Between April 2019 and October 2021, 175 patients were assigned to group A (N = 88) or group B (N = 87). One patient in group B who experienced chylothorax was excluded from the study. Respiratory-related adverse events were observed in 10 patients (11.4%) in group A and 12 patients (14.0%) in group B (P = .008). The frequencies of thoracentesis or chest tube reinsertion were not significantly different (8.0% and 9.3% in groups A and B, respectively, P = .752). Additionally, the duration of chest tube placement was significantly shorter in group A than in group B (median, 2 vs 3 days; P < .001). No significant difference between groups A and B was found in postoperative hospital stay (median, 6 vs 7 days, P = .231). CONCLUSIONS: Early chest tube removal, regardless of drainage volume, was safe and feasible in patients who underwent anatomic pulmonary resection.

Typical carcinoid in right middle lobe of pulmonary hypoplasia.

BACKGROUND: Pulmonary typical carcinoid occurring in hypoplasia of the right middle lobe is very rare. CASE PRESENTATION: A routine examination's chest X-ray revealed an abnormal shadow in the right middle lung field of an 82-year-old Japanese woman. A chest computed tomography scan showed a solid 2.5 × 2.0-cm nodule in the very small right middle lobe. A trans-bronchial lung biopsy of the mass in the right middle lobe was performed; it revealed atypical cells with round nuclei growing in multiple foci, and immunostaining was positive for chromogranin A, synaptophysin and CD56, suggesting pulmonary carcinoid. The preoperative clinical diagnosis of primary lung cancer, cT1cN0M0 stage IA3 was considered. A right middle lobectomy and mediastinal lymph node dissection were performed by video-assisted thoracic surgery. Intraoperatively, the middle lobe of the right lung was very small, with 1- to 2-mm-dia. pulmonary arteries and veins that were considered hypoplastic. The final histopathological diagnosis was typical carcinoid, pT2aN0M0 stage IB based on the presence of pleural invasion. CONCLUSIONS: Including the present patient, only nine cases of lung cancer occurring within pulmonary hypoplasia have been reported, most of which were typical carcinoid.

Dynamic transition of molecular subtypes in relapsed small cell lung cancer treated with multimodal therapy: A case report.

Several transcription factors in small cell lung cancer (SCLC), including achaete-scute homolog 1 (ASCL1) and neurogenic differentiation factor 1 (NEUROD1), contribute to rapid tumor growth and early metastatic dissemination. Recent studies suggested that these molecular subtypes represent neuroendocrine differentiation in dynamic SCLC evolution. In the present case, a 62-year-old man was diagnosed with limited disease SCLC originating from the right upper lobe. Biopsy specimens were positive for ASCL1 but negative for NEUROD1. Six months after concurrent chemoradiotherapy and prophylactic cranial irradiation, the primary tumor had regrown and salvage surgery was performed. The pathological diagnosis was recurred SCLC, and postoperative histopathology was positive for both ASCL1 and NEUROD1. The patient was subsequently followed up; however, he had multiple bone metastases 9 months after surgery. It was speculated that the shift to NEUROD1-high expression in tumor cells surviving concurrent chemoradiation therapy may be related to the poor outcome after combined modality treatment.

Clinical significance of MYC family protein expression in surgically resected high-grade neuroendocrine carcinoma of the lung.

OBJECTIVES: MYC family genes including MYC, MYCN, and MYCL are amplified and overexpressed as oncogenic drivers in high-grade neuroendocrine carcinoma of the lung (HGNEC), but little is known about their clinical significance. This study evaluated the prognostic impact of MYC family protein expression in patients with surgically resected HGNEC. METHODS: Immunohistochemical analyses were performed on 83 resected specimens of HGNEC using antibodies against MYC family proteins (c-MYC, n-MYC, and l-MYC). When nuclear staining of any intensity in ≥10% of tumor cells showed immunoreactivity with any one or more of c-MYC, n-MYC, or l-MYC, the specimens were defined as MYC family-positive. RESULTS: A total of 83 patients were analyzed. MYC family-positive status was observed in 33.7% (28 of 83 cases) and was not correlated with clinicopathological factors. The protein expression was mutually exclusive and no duplicate cases were observed. A log-rank test showed that MYC family-positive status was significantly associated with shorter overall survival (OS) (p = 0.003) and recurrence-free survival (RFS) (p = 0.039). According to Cox multivariate analysis, MYC family-positive status had a significant effect on shorter OS (hazard ratio [HR] = 2.217, 95% confidence interval [CI] 1.179-4.169, p = 0.014) and RFS (HR = 1.802, 95% CI 1.014-3.202, p = 0.045). In patients with pathological stage I, MYC family-positive status also showed significantly poor OS (HR = 2.847, 95% CI 1.236-6.557, p = 0.014) and RFS (HR = 2.088, 95% CI 1.006-4.332, p = 0.048) in the multivariate analysis. CONCLUSIONS: MYC family protein expression could be an independent unfavorable prognostic factor in patients with surgically resected HGNEC.